Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

A comparison of the efficiencies of bromates and nitrates in the separation of the rare earth elements… Wylie, Dorothy Elinore 1933

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata

Download

Media
831-UBC_1933_A8_W8_C6.pdf [ 4.62MB ]
Metadata
JSON: 831-1.0061943.json
JSON-LD: 831-1.0061943-ld.json
RDF/XML (Pretty): 831-1.0061943-rdf.xml
RDF/JSON: 831-1.0061943-rdf.json
Turtle: 831-1.0061943-turtle.txt
N-Triples: 831-1.0061943-rdf-ntriples.txt
Original Record: 831-1.0061943-source.json
Full Text
831-1.0061943-fulltext.txt
Citation
831-1.0061943.ris

Full Text

•A. COMPARISON. OF .THE EFFICIENCIES OF BROMATES AND NITRATES IN THE SEPARATION OF THE RARE EARTH ELEMENTS FROM ONE ANOTHER  •  • ' by D o r o t h y S l i n o r e Wylie  ooo o o  -A; :THES IS; SUBWITIED FOR TEE DEGREE OF M A S T E R  OF  APR T S.  IN.THE DEPARTMENT  C H E M I S T R  Y  o o o oo o  THE UNIVERSITY OF BRITISH COLUMBIA A p r i l , 1952  TABLE OF CONTENTS..  A. I n t r o d u c t i o n .  Page  1  B. H i s t o r i c a l . .  . Page  2  C. E x p e r i m e n t a l  Page  5  D. P r e p a r a t i o n  of t h e S a l t s . . .  S e r i e s A.A. N i t r a t e s S e r i e s B.B. Bromates. E. P r e p a r a t i o n F. D i s c u s s i o n  o f Samples . . > of R e s u l t s .  . . Page. 7 >  Page  7  Page  7  Page Page 11  G. Summary  Page 13.  Plate I  Page 15  9  (1)  A COMPARISON OF THE EFFICIENCIES OF 3R0MATES AND NITRATES IN THE SEPARATION OF THE RARE EARTH ELEMENTS FROM ONE ANOTHER»  A.  INTRODUCTION: Increased i n t e r e s t  i s b e i n g t a k e n i n the elements  of t h e Rare E a r t h Group Owing t o t h e i r growing  impor-  tance i n i n d u s t r y and t o t h e f a c t t h a t they o f f e r  interest-  i n g s t u d i e s from t h e v i e w p o i n t o f atomic s t r u c t u r e , etc.  origin  I n e v e r y c a s e , however, p r o g r e s s i s r e t a r d e d owing  to t h e extreme d i f f i c u l t y w i t h which, they may be s e p a r a t e d from one a n o t h e r . the i n d i v i d u a l  The i s o l a t i o n o r i d e n t i f i c a t i o n of  jse&ibers of t h i s group covers a p e r i o d ox  some'130 y e a r s , t h e f i r s t member being d i s c o v e r e d i n 17S4 whereas t h e e x i s t e n c e of the l a s t was o n l y demonstrated  i n 1926. D u r i n g t h i s p e r i o d a g r e a t many methods have been  used f o r t h e s e p a r a t i o n and p u r i f i c a t i o n of t h e elements, methods i n v o l v i n g  i n t h e main p a r t d i f f e r e n c e s i n t h e  s o l u b i l i t i e s o f s i m p l e or d o u b l e s a l t s of t h e elements, or d i f f e r e n c e s i n t h e b a s i c i t i e s o f t h e o x i d e s . r e s u l t the i n d i v i d u a l been i s o l a t e d  As a  members of the e n t i r e group have  i n s u f f i c i e n t amounts t o a l l o w o f t h e i r  i d e n t i f i c a t i o n as elements, even though v e r y few have 1. H a r r i s w i t h H o p k i n s — J .A. C-S. > 48, 1586.  (2).  been p r e p a r e d and  i n . a s t a t e 02 a t o m i c p u r i t y i n any q u a n t i t y ,  these only a f t e r extensive f r a c t i o n a l  crystallisations.  The methods used, have n a t u r a l l y v a r i e d w i t h each i n v e s t i g a t o r and as a r e s u l t t h e l i t e r a t u r e i s f i l l e d w i t h c o n f l i c t i n g s t a t e m e n t s as t o the r e l a t i v e e t c . , and w h e r e a s . s e p a r a t i o n complished  solubilities,  o f t h e elements has been a c -  by v a r i o u s means, t h e r e i s no c l a i m rcade as t o  t h e method used b e i n g t h e most e f f i c i e n t one.  The r e s u l t  has been t h e r e f o r e t o use f o r p r e l i m i n a r y s e p a r a t i o n s , methods t h a t have been shown t o b e f a i r l y s u c c e s s f u l , and the g e n e r a l s e p a r a t i o n s the f i n a l p u r i f i c a t i o n g e n e r a l l y depends 011 t h e p e r s o n who i s w o r k i n g on t h e p a r t i c u l a r problem* B. _ HISTORICAL: D u r i n g the c o n c e n t r a t i o n of i l l i n i u m i t was o b v i o u s that although  a great' d e a l o f d a t a was a v a i l a b l e  methods f o r p r o d u c i n g  regarding  a s e p a r a t i o n of the rare e a r t h e l -  ements f r o m one a n o t h e r ,  any t h i n g i n t h e way o f a compar-  a t i v e s t u d y o f these methods was l a c k i n g * P r e l i m i n a r y s e p a r a t i o n o f cerium group e a r t h s i s g e n e r a l l y a c c o m p l i s h e d b y the f r a c t i o n a l  crystallization  of a double s a l t , u s u a l l y the double magnesium n i t r a t e . I n t h e case o f the y t t r i u m . g r o u p  earths, f r a c t i o n a t i o n of  the bromates appears t o be the method most f r e q u e n t l y used  (5)  a l t h o u g h t h e s i m p l e n i t r a t e s have a l s o been recommended. Our or;n i n t e r e s t , as has been p o i n t e d out i n p r e v i o u s p a p e r s , i s d i r e c t e d c h i e f l y towards t h e f i n d i n g o f a more e f f i c i e n t method f o r t h e c o n c e n t r a t i o n o f i l l i n i u m t h a n was u s e d f o r i t s i s o l a t i o n .  Consequently our e f f o r t s have  been d i r e c t e d towards a c o m p a r a t i v e s t u d y o f t h e e f f e c t o f c r y s t a l . l i z i n g as many d i f f e r e n t s a l t s as p o s s i b l e i n the hope t h a t some one s a l t might prove E o r e e f f e c t i v e i n p e r m i t t i n g of a c o n c e n t r a t i o n o f a p a r t i c u l a r element than the o t h e r s .  I n e v e r y case t h e r e f o r e i d e n t i c a l m a t e r i a l  was u s e d , a n d t h e c o n d i t i o n s of c r y s t a l l i z a t i o n m a i n t a i n e d a s n e a r l y t h e same i n a l l c a s e s a s p o s s i b l e .  The e f f e c t  of t h e f r a c t i o n a t i o n was i n each case observed b y comp a r i n g t h e a b s o r p t i o n s p e c t r a of s o l u t i o n s made up from a d e f i n i t e volume of s a t u r a t e d s o l u t i o n from each  fraction.  The r e s u l t s from s u c h a s t u d y o f t h e s p e c t r a o b t a i n e d  from  v a r i o u s s e r i e s of s a l t s o f the--cerium group e a r t h s have 2 2,5. been r e p o r t e d , and i t was p o s s i b l e from s u c h a comparative study.-to n o t e t h a t c e r t a i n s a l t s a r e more e f f e c t i v e i n b r i n g i n g about a r a p i d s e p a r a t i o n o f c e r t a i n elements than are the others.  Consequently a g r e a t d e a l o f time may be  saved by s e l e c t i n g the s a l t t o be used, f o r p r e l i m i n a r y s e p a r a t i o n a s c a r e f u l l y as t h a t f o r t h e f i n a l  purification.  A s i m i l a r i n v e s t i g a t i o n as t o the r e l a t i v e e f f e c t s 2. Pearce w i t h H a r r i s — T . R . S - C > Sec. I l l , 1930, 145. 3, W y l i e -vi'th H a r r i s — T . R . S . C , Sec. I l l , 1951, 107.  (4)  of the f r a c t i o n a l c r y s t a l l i z a t i o n  of s a l t s of the r a r e  e a r t h s o b t a i n e d , from g a d o l i n i t e was  c a r r i e d out.  The  s a l t s u s e d were t h e s i m p l e n i t r a t e s and t h e b r o m a t e s these  as  have p r o v e d more e f f e c t i v e i n t h e s e p a r a t i o n of t h e  y t t r i u m group  earths.  The f r a c t i o n a l  crystallization  i n t r o d u c e d b y James i n h i s c l a s s i c a l group e a r t h s .  I n .'his l a t e r  the Rare E a r t h s attacking  B  was  work on t h e y t t r i u m  paper on t h e "Separation o f  h e sugges.ts f o u r d i f f e r e n t  methods f o r  t h e c r u d e o x a l a t e s , d e p e n d i n g on t h e c o n c e n t r a t i o n  of the l a t t e r .  F o r the s e p a r a t i o n o f the crude y t t r i u m  e a r t h s he recommends the f r a c t i o n a l bromates.  of the bromates  He c o n v e r t e d t h e  sulphates by t r e a t i n g  c r y s t a l l i s a t i o n of the  o x a l a t e s t o t h e anhydrous  them w i t h a s l i g h t .excess o f s u l -  p h u r i c a c i d and h e a t i n g u n t i l c e a s e d t o be e v o l v e d .  a l l l u s e s of sulphuric  The i g n i t e d  i n c o l d water and a f a i r l y  s u l p h a t e s were d i s s o l v e d  s t r o n g s o l u t i o n o f them w e r e .  a d d e d t o b a r i u m bromate, c o v e r e d w i t h a l a y e r h e a t e d on a s t e a m b a t h . p o s i t i o n was  c r y s t a l s formed fractionally  o f w a t e r and  The w h o l e was f i l t e r e d when decom-  completed and the b a r i u m s u l p h a t e w e l l  w i t h h o t water-*  acid  washed  The c l e a r l i q u i d was e v a p o r a t e d u n t i l and the..mother  l i q u o r and c r y s t a l s  crystallised..  were •  U s i n g t h i s method James f o u n d t h a t ' S a m a r i u m and 4, G. J a m e s — J . A . C-S. , 1208, 50,182.; 1912, 34,757.  -  <6>  GafioliEium r a p i d l y s e p a r a t e d i n t h e l e a s t  soluble  crystals,  * f o l l o w e d b y D y s p r o s i u m , Holmium a n d Y t t r i u m , whereas t h e most s o l u b l e f r a c t i o n s c o n t a i n e d p r a c t i c a l l y p u r e E r b i u m , T h i s method h a s been u s e d e x t e n s i v e l y s i n c e by r a r e e a r t h w o r k e r s i n t h e Y t t r i u m group-. Fractional crystallization . -6., . first  u s e d by Dewarcay who found  of the n i t r a t e s  was  t h a t t h i s method was  p a r t i c u l a r l y e f f e c t i v e when t h e m i x t u r e  of earths  con-  t a i n e d no e l e m e n t o f a t o m i c w e i g h t l e s s t h a n t h a t o f d^rpsiuBU  ,  B a u r and Marc found  t h e method v e r y e f -  f i c i e n t f o r s e p a r a t i n g g a d o l i n i u m from y t t r i u m and i t has s i n c e been u s e d e x t e n s i v e l y b y U r b a i n and o t h e r s . Q. • EXPEHIKSITAL::. S t a r t i n g w i t h t h e c r u d e o r e , t h e r a r e e a r t h s were e x t r a c t e d and a f t e r  p u r i f i c a t i o n s a m p l e s o f t h e s e were  t a k e n and c o n v e r g e d i n t o b r o m a t e s and n i t r a t e s .  Fractional  c r y s t a l l i z a t i o n o f t h e two s e r i e s was c a r r i e d o u t i n o r d e r t o determine-which.salt brought about t h e b e t t e r  separation  o f members o f .the y t t r i u m g r o u p . The m a t e r i a l u s e d h a d i t s s o u r c e i n N o r w e g i a n Gadolinit-e.  The e a r t h s w e r e ' e x t r a c t e d w i t h  hydrochloric  a c i d o r c o n c e n t r a t e d sodium h y d r o x i d e f o l l o w e d b y n i t r i c a c i d e x t r a c t i o n , t h e s e '-extract&nts h a v i n g b e e n shown t o be . . . 7, t h e 'most e f f i c i e n t ones f o r t h i s m i n e r a l . Thife: l i q u o r 6v Bernarcy.y—Cozra?. B e n d . , 1 8 9 6 , 1 2 2 , 728.6, B a u r & M a r c — B e r . , 1 9 0 1 , 54, 2460. 7. Horn's-Peorce ~T.H.S-C". s S e c I I I , 1 9 2 9 , 6 1 .  (6)  containing  the e a r t h s was then d i l u t e d , and t h e e a r t h s  p r e c i p i t a t e d .as t h e h y d r o x i d e s by ammonia. •  The m i x t u r e was f i l t e r e d , washed- t h o r o u g h l y , and  t h e n t a k e n i n t o s o l u t i o n i n t h e Biinirsim amount of n i t r i c acid. the  The r e s u l t i n g s o l u t i o n was d i l u t e d , h e a t e d , and  o x a l a t e s p r e c i p i t a t e d by t h e a d d i t i o n of excess o f  saturated  oxalic acid solution.  washed s e v e r a l and  These were f i l t e r e d ,  t i m e s w i t h w a t e r and a g a i n f i l t e r e d ,  dried  i g n i t e d to the oxides i n a muffle. S i n c e the presence o f cerium r e n d e r s t h e p r e p -  a r a t i o n o f t h e torornate d i f f i c u l t , owing t o t h e a c i d c h a r a c t e r o f s o l u t i o n s of c e r i u m s u l p h a t e , i t i s n e c e s s a r y t o remove even t h e s m a l l amounts o f cerium which a r e present i n gudolinit-e* containing  The o x i d e s were e x t r a c t e d  with n i t r i c acid  a l i t t l e hydrogen p e r o x i d e and t h e s m a l l  amounts of i n s o l u b l e m a t e r i a l was d i l u t e d t o s e v e r a l  filtered  out.  The f i l t r a t e  tiroes i t s o r i g i n a l volume and  b r o u g h t t o n e u t r a l i t y by t h e a d d i t i o n o f ammonia. ships  and s o l i d  Marble  p o t a s s i u m b r ornate were no?; added and t h e  s o l u t i o n brought t o b o i l i n g .  A f t e r allowing.the mixture  t o c o o l j t h e b a s i c c e r i u m was f i l t e r e d out and t h e e a r t h s i n the s o l u t i o n p r e c i p i t a t e d as the h y d r o x i d e s w i t h •ammonia* •  ..•  -These were washed t h o r o u g h l y by d e c a n t a t i o n and then dissolved i n n i t r i c acid*  The s o l u t i o n was t h e n  e v a p o r a t e d u n t i l t h e n i t r a t e s c r y s t a l l i z e d out f o l l o w e d  by t h e i r s o l u t i o n i n r/ater unci the p r e c i p i t a t i o n of t h e e a r t h s as o x a l a t e s w i t h subsequent i g n i t i o n t o t h e o x i d e s . De -PREPARATION OF THE SALTS.. Samples o f the p u r i f i e d o x i d e s w e i g h i n g 250 grams were • t a k e n i n each  case-,  •SERIES .A.A. NITRATES-. The o x i d e s were moistened w i t h water and t h e n warmed w i t h c o n c e n t r a t e d effected.  n i t r i c a c i d u n t i l s o l u t i o n was  The s o l u t i o n was t h e n e v a p o r a t e d u n t i l  crys-  t a l l i z a t i o n was a l m o s t complete upon c o o l i n g t o room temperature.  The s a l t was then c r y s t a l l i z e d from c o n -  c e n t r a t e d n i t r i c a c i d u n t i l a s e r i e s of e i g h t f r a c t i o n s h a d been b u i l t u p  s  new f r a c t i o n s b e i n g s t a r t e d w i t h  s i x t h , eleventh., s i x t e e n t h , t w e n t y - f o u r t h , f o r t y second a n d f i f t i e t h p o u r i n g s , making a t o t a l o f f i f t y - t w o  crystal-  l i z a t i o n s i n t h e case of f r a c t i o n one, cold two i n t h e case o f f r a c t i o n seven. .-. ~ SF;RIPS B.B. BROMATES. - - 8-,  I n a paper p u b l i s h e d by H a r r i s i t was p o i n t e d out t h a t the c l a s s i c a l method f o r t h e p r e p a r a t i o n o f the bromates i s t h a t of James.  I t was a l s o shown how-  e v e r , that d i f f i c u l t y is/encountered  when t h i s method i s  used f o r t h e p r e p a r a t i o n of the bromates o f t h e cerium 8. J . A . C S , , 53, 2475, 1951*.  (8).  group earths  s  when l a r g e amounts o f t h e more b a s i c  members a r e p r e s e n t .  A t t h e same t i m e t h e method  invol-  v i n g as i t does t h e d e c o m p o s i t i o n o f the s u l p h a t e  radical  by  the oxalate i o n , I s o b j e c t i o n a b l e from the standpoint  cf  t h e c o p i o u s e v o l u t i o n o f fumes > and t h e n e c e s s i t y f o r  .the  s o l u t i o n of the r e s u l t i n g sulphates The  features apply  s  i n I c e water*  method by H a r r i s e l i m i n a t e d t h e s e  a n d s o i t was deemed a d v i s a b l e  i t to t h e y t t r i u m group The  objectionable  t o attempt t o  earths.  second sample o f oxides  was m o i s t e n e d .with  w a t e r t o a l l o w o f r e a d y p e n e t r a t i o n b y t h e a c i d and. t h e n treated-with small portions lowing  the liquor  a d d i t i o n of a c i d ,  o f s u l p h u r i c a c i d (1:5)'  t o reach n e u t r a l i t y b e f o r e i l l en  a l -  subsequent  t h e p o i n t had been reached a t  which t h e l i q u o r remained acid., the m i x t u r e  was g e n t l y  h e a t e d u n t i l n e u t r a l i t y was a g a i n a t t a i n e d . ' The a d d i t i o n o f a c i d ?;as t h e n c a r r i e d o u t o n a h o t p l a t e u n t i l acid solution persisted. the  mixture  a  faintly  When s u c h a c o n d i t i o n was r e a c h e d  was e v a p o r a t e d t o d r y n e s s .  When d r y , t h e  s u l p h a t e s w e r e removed a n d p u l v e r i s e d , a n d i g n i t e d i n small portions with frequent until salt  s t i r r i n g over a strong  flame  a l l e x c e s s a c i d h a d b e e n removed a n d t h e a n h y d r o u s obtained.  T h i s v/as q u i c k l y t r a n s f e r r e d t o a d r y ,  p r e v i o u s l y weighed  container, roughly  weighed and t r a n s -  •ferred immediately while s t i l l was  hot t o a b e l l j a r which  evacuated. Froia t h e w e i g h t of t h e sulphates' t h e amount o f  w a t e r n e c e s s a r y f o r t h e i r s o l u t i o n was c a l c u l a t e d a n d measured i n t o a l a r g e b e a k e r ,  fhen cool  w e r e removed i n s m a l l  and s p r i n k l e d w i t h  orous s t i r r i n g  portions  the sulphates vig-  i n t o t h e w a t e r where t h e y d i s s o l v e d  readily giving a solution neutral A saturated  fairly  to litmus.  s o l u t i o n o f b a r i u m bromate'was • p r e -  p a r e d | t h e s u l p h a t e was a d d e d t o t h i s i n s m a l l  portions  m a k i n g s u r e t h e r e was a l w a y s a n e x c e s s o f b a r i u m i o n i n s o l u t i o n a n d t h e s o l u t i o n was k e p t a t 100° a n d s t i r r e d mechanically. the  b a r i u m s u l p h a t e p r e c i p i t a t e was f i l t e r e d o u t . The  was  When a l l t h e s u l p h a t e s o l u t i o n was a d d e d ,  s o l u t i o n of rare  e a r t h broisates  thus  e v a p o r a t e d s l o w l y on a steam b a t h u n t i l  obtained  crystals  f o r m e d , t h e n t h e b r o m a t e s were p l a c e d i n t h e c o l d and allowed to • crystallize-.F*- PREPARATION -OF SAMPLES: As  was r e p o r t e d i n n r e v i c u s p a p e r s , i n o r d e r t o  compare t h e r e l a t i v e s e p a r a t i o n s over the e n t i r e  series  at  possible  the  the f i n a l  c r y s t a 11 i za t i o n a n d t o a s c e r t a i n  if  r e l a t i v e amounts o f t h e v a r i o u s e a r t h s i n each f r a c -  t i o - n , - ea-ch- s e r i e s was t a k e n a n d a c i d o r w a t e r added t o the  f r a c t i o n s and re c r y s t a l l i s a t i o n e f f e c t e d  so that  the '  volumes o f l i q u o r and same.  c r y s t a l s were a p p r o x i m a t e l y  S i n c e the a c i d r a d i c a l has  absorption spectra advisable  of r a r e e a r t h  a marked e f f e c t on s o l u t i o n s I t was  t o c o n v e r t the s a l t s i n each case t o  n i t r a t e s f o r spectroscopic f r a c t i o n s of the two  the  examination.  The  s e r i e s were t h e r e f o r e  the  deemed •  the  Individual  maintained at  c o n s t a n t t e m p e r a t u r e f o r s e v e r a l hours i n o r d e r t o p e r m i t of e q u i l i b r i u m between the s o l i d reached.  10  c. c. samples of the s a t u r a t e d  then withdrawn, t r a n s f e r r e d p o r a t e d to d r y n e s s . and  The  liquid  dissolved  s o l u t i o n s were  t o l a r g e b e a k e r s and  The  p r e c i p i t a t e s were washed w i t h w a t e r ,  i n a l i t t l e n i t r i c a c i d , the s o l u t i o n d i l u t e d  the r a r e e a r t h  to the oxides.  o x a l a t e s p r e c i p i t a t e d from hot s o l -  The  These were th en i g n i t e d  o x i d e s a f t e r weighing,:  :  f o r reference  p u r p o s e s , \?ere moistened w i t h a l i t t l e water andc o n c e n t r a t e d n i t r i c a c i d and  They were.taken up - p e r o x i d e and 5 cc. . and  eva-  r e s i d u e s were t a k e n up i n water  u t i o n by means of o x a l i c a c i d .  in  being  the e a r t h s p r e c i p i t a t e d as the h y d r o x i d e s by means  of ammonia.  and  and  dissolved  evaporated to dryness«  In water containing  a l i t t l e hydrogen  evaporated s e v e r a l times to expel 1 a c i d .  of d i s t i l l e d water were added to each d r i e d sample  warmed s l i g h t l y  to e f f e c t s o l u t i o n .  Except i n the  cases of f r a c t i o n s seven and e i g h t o f the n i t r a t e s e r i e s , c l e a r s o l u t i o n s were o b t a i n e d .  I n 'these samples, however*  (II)  a bcsic salt  p r e c i p i t a t e d and  was  filtered  sequently with the  e x c e p t i o n of these  sample r e p r e s e n t e d  t h e amount o f r a r e e a r t h s  i n 10 in  c c  of the  5 c«o.  original  o f s o l u t i o n as  photographed through  salt  two  out.  a 5 era. cell.  The The  recorded  were c o m p a r e d t o t h e  arc,  a l 3 o to the a b s o r p t i o n obtained  and  solutions  P. DISCUSSION OP The  the  each  contained now  contained  s o l u t i o n s were  a b s o r p t i o n bands  spectrum of a s t a n d a r d from  same  iron  standard  o f n e o d y s i u r a , samarium, e r b i u m and h o i  photographed through  cussed  fractions,  s o l u t i o n and  the n i t r a t e .  Con-  Mum.,  cell.  RESULTS:  photographs obtained  above a r e r e p r o d u c e d  from the s o l u t i o n s d i s -  i n Plate I.  of these a b s o r p t i o n s p e c t r a i s  egre  An i t e r p r e t a t i o n  complicated  than  in  the case of a s e r i e s  composed o f e l e m e n t s o f t h e  group a l o n e .  s e r i e s discussed i n t h i s paper, i n  In the  a d d i t i o n to having  members o f t h e y t t r i u m g r o u p  present  s m a l l a m o u n t s of  causing  o v e r l a p p i n g of a b s o r p t i o n bands.  eral  cerium  cerium  earths  group elements are  present  Likewise,  sev-  members o f t h e y t t r i u m g r o u p e a r t h s y i e l d s o l u t i o n s  that have but  little  o r no  r e g i o n o f the  spectrum.  a b s o r p t i o n i n the  I t thus  i s p o s s i b l e at t h i s  s t a g e t o o b t a i n o n l y a g e n e r a l i d e a as t o the e f f e c t i v e n e s s o f each s a l t individual  members o f t h e  visible  relative'  i n --reducing s e p a r a t i o n s rare  earth  group.  of  (IB)  The  solutions  o f t h e bromates v a r i e d  from c o l o r l e s s i n the the  t h i r d one,  last  two.  2 and  3,  f i r s t f r a c t i o n , to a d a r k p i n k  f a d i n g away t o a v e r y p a l e  The  i n colour  oxalates  tint  In  th  f r o m f r a c t i o n 1 were white  p i n k , f r o m 4 and  5.  w h i t e . and  f r o m S,  in e fr  s  ? and  om 8  pink, •The a b s o r p t i o n rapid concentration  spectra-indicates  o f neodymium and  head f r a c t i o n s , w h e r e a s t h e least  erbium concentrates i n  s o r p t i o n b a n d s w o u l d i n d i c a t e the  in Fractions  2 and  3, D y s p r o s i u m i n F r a c t i o n  a colourless earth  F r a c t i o n 8 and  Erbium i n F r a c t i o n s  The  some o f t h e The  a l l of  the  ? and  of  Needy nil urn 4,•fiolmium  8. o f most use  f r a c t i o n a t i o n of a  Y t t r i u m Group earths  in  series  together  with  c e r i u m Group. final  s o l u t i o n s f r o m the n i t r a t e s v a r i e d  a l m o s t c o l o u r l e s s i n F r a c t i o n 1 t o a deep p i n k 5.  ab-  Samarium from Eolmiuin, Y t t r i u m  Erbium i n a p r e l i m i n a r y  containing  the  (possibly yttrium): i n  b r o m a t e s w o u l d a p p e a r t o be  s e p a r a t i n g Neodymium and and  concentration  Samarium, T e r b i u m and  i n F r a c t i o n 5,  is a  samarium-in the  A p r e l i m i n a r y s t u d y of  soluble fractions.  E u r o p i u m i n F r a c t i o n 1,  that there  in  from  Fraction  F r a c t i o n 6 showed a s l i g h t o r a n g e c o l o u r , . F r a c t i o n ?  -deep o r a n g e , and p h o t o g r a p h i n g the  F r a c t i o n 8 a deep y e l l o w  colour.  absorption S p e c t r a ' o f these  In  solutionis  a  (IS);  i t was i m p o s s i b l e t o o b t a i n i x n i f or.; i n t e n s i t y i n t h e l a s t t h r e e f r a c t i o n s owing t o t o t a l a b s o r p t i o n f r o m yellow t o v i o l e t .  I n t h e p h o t o g r a p h s p r o d u c e d , t h e l&wer  f i g u r e represents the r e s u l t s obtained b y prolonged exposure of the t h r e e lower f r a c t i o n s .  The i n t e n s i t y o f  t h e bands i n t h e s e c a s e s cannot t h e r e f o r e be used f o r c o m p a r i s i o n w i t h t h e o t h e r exposure-??,. The n i t r a t e s b r i n g about a t o t a l l y  different  order o r sepuration t o that produced by the f r a c t i o n a l c r y s t a l l i z a t i o n o f t h e bromates.  Terbium,  Europium,  D y s p r o s i u m and Samarium appear t o c o n c e n t r a t e  i n t h e head  f r a c t i o n s f o l l o w e d b y Holroiuia, E r b i u m a n d f i n a l l y dyaiium, a l t h o u g h i t i s d i f f i c u l t  Neo-  to i n t e r p r e t the Spectra  of t h e l a s t t h r e e f r a c t i o n s a s i n d i c a t e d  previously.  The v a l u e of t h e n i t r a t e s would appear t o be i n .the r a p i d s e p a r a t i o n o f S a m a r i u m f r o m Beodymium i n a n Y t t r i u m group mixture i n which these elements a r e present. I t w o u l d a l s o p r o v e a n e f f e c t i v e means o f s e p a r a t i n g Terbium, E u r o p i u m a n d p o s s i b l y G a d o l i n i u m f r o m s u c h a mixture, G« SUMMARY:. • k p r e l i m i n a r y study of the e f f e c t ' o f  crystallisation  o f • i d e n t i c a l m a t e r i a l a s t h e b r o i a a t e s , and a s t h e n i t r a t e s has b e e n made.  Tiie o r d e r series differs.  of s o l u b i l i t i e s  of the s a l t s i n each  For the r a p i d separation  o f Erbium, o r  o f Neodj'mium and S a m a r i u m f r o n t an Y t t r i u m g r o u p the bromates  mixture  are- t o b e recommended f o r t h e p r e l i m i n a r y  separation.  '  ' The n i t r a t e s a p p e a r t o o f f e r a s p l e n d i d means, for  t h e r a p i d c o n c e n t r a t i o n o f Europium, T e r b i u m a n d  Gadolinium from a general  mixture*  (15)  

Cite

Citation Scheme:

        

Citations by CSL (citeproc-js)

Usage Statistics

Share

Embed

Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                        
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            src="{[{embed.src}]}"
                            data-item="{[{embed.item}]}"
                            data-collection="{[{embed.collection}]}"
                            data-metadata="{[{embed.showMetadata}]}"
                            data-width="{[{embed.width}]}"
                            async >
                            </script>
                            </div>
                        
                    
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:
http://iiif.library.ubc.ca/presentation/dsp.831.1-0061943/manifest

Comment

Related Items